Catalyst for hydrocarbon conversion

ABSTRACT

This invention relates to a method of preparing a catalyst useful in hydrocarbon conversion such as alkylation and polymerization. More particularly, this invention relates to the polymerization of polymerizable hydrocarbons e.g. propylene and the alkylation of alkylatable hydrocarbons e.g. benzene in the presence of an alumina catalyst activated with an organic species having at least two carbon atoms per molecule, and chlorine or bromine in suitable proportions, or with a mixture of multicarbon activators and chlorine and bromine.

Unitedv States Patent [72] Inventors [54] CATALYST FOR HYDROCARBONCONVERSION 10 Claims, No Drawings 52 u.s.c| 260/671, 260/683.15, 252441, 252 442 51 lnt.Cl C07c 3 00, C07c 3 50 50 Field ofSearch 252 442;

[56] References (Iited UNITED STATES PATENTS 3,268,618 8/1966 Fletcher260/683. 15

Primary Examiner-Patrick P. Garvin Assistant ExaminerPhilip M. FernenAttorneysK. E. Kavanaugh, Thomas H. Whaley and H. L.

Madinger ABSTRACT: This invention relates to a method of preparing acatalyst useful in hydrocarbon conversion such as alkylation andpolymerization. More particularly, this invention relates to thepolymerization of polymerizable hydrocarbons e.g. propylene and thealkylation of alkylatable hydrocarbons e.g. benzene in the presence ofan alumina catalyst activated with an organic species having at leasttwo carbon atoms per molecule, and chlorine or bromine in suitableproportions, or with a mixture of multicarbon activators and chlorineand bromine.

CATALYST FOR HYDROCARBON CONVERSION BACKGROUND OF THE INVENTION Highlyactive hydrocarbon conversion catalysts particularly useful forisomerization can be prepared by the method of copending applicationSer. No. 600,02l,now abandoned Dec. 8, 1966 entitled Catalyst forHydrocarbon Conversion" of John H. Estes, Robert M. Suggitt and StanleyKravitz assigned to the assignee hereof."These catalysts are prepared'bycontacting a composite of alumina and platinum with an organic compoundin the presence of chlorine or bromine at a temperature of about 200 to800 F. A catalyst consisting essentially of about 0.01 to about 2.0weight percent platinum and about 3.0 to about 15.0 weight percentchlorine is thus prepared. Catalysts useful in polymerization ofpolymerizable compounds especially lower olefms do not require thepresence of platinum therein or other noble metals. This is also truefor alkylation catalysts useful. in alkylation of aromatic compoundse.g. benzene.

SUMMARY OF THE INVENTION It is an object of this invention, therefore,to prepare such STATEMENT OF THE INVENTION Broadly, this inventioncontemplates a method for preparing a catalyst consisting essentially ofcatalytically active alumina, and chlorine or bromine, which comprisescontacting alumina with chlorine or bromine and an organic compound or amixture of organic compounds having at least two carbon atoms each attemperatures of between 200and 800 F., preferably between 450 F. and 650F.

DESCRIPTION OF PREFERRED EMBODIMENTS Since at temperatures above 700 F.there is a tendency for aluminum chloride formation, the flow rate ofthe gases through the alumina and the pressure on the system should beregulated when temperatures above 650 F. are employed. The process ofour invention is most suitably performed at atmospheric pressurealthough subatmospheric and superatmospheric pressures can be employed.We prefer to use atmospheric or slight superatmospheric pressure becauseit. minimizes cost attendant with the employment of pressuressubstantially below or above atmospheric pressure. We have found thatusing chlorine or bromine with an organic compound, or mixtures oforganic compounds at temperatures between 450 and 650 F. and atmosphericpressure, there is provided a highly active catalyst useful in thealkylation of aromatics and polymerization of olefins. Olefins withintherange of C -C are polymerized in good yield using the alumina catalystprepared by the process of this invention. The aforementioned specificpolymerizable hydrocarbon, it should be understood, is merely exemplaryof the polymerizable hydrocarbons which can be polymerized using thecatalyst of this invention.

The catalyst prepared by our invention consists essentially ofcatalytically active alumina, and about 3.0 to about 15.0 percent byweight chlorine or bromine. It is prepared by using an organic compound,or mixture of organic compound as activating agents in conjunction withchlorine and/or bromine. The organic compound comprises at least twoatoms of carbon, X atoms of hydrogen, Y atoms of chlorine and/orbromineand may or may not contain oxygen or sulfur. Either X or .Y may be zero.The practical optimum mole ratio of molecular chlorine and/or bromine tothe organic compound must be greater than -Y/2 if X2Y(X is equal to orgreater than Y) or greater than zero if X Y (X is less than Y). Theamount ofchlorine or bromine should be greater if the organic compoundcontains sulfur. Specifically, if there are Z atoms of sulfur in theorganic compound the mole ratio of chlorine and/or bromine (Y) toorganic compound should be greater than X+2Z'Y/2 if X+2ZZ Y or greaterthan zero if X+2Z Y.

In particular, organic chloride activating agents which can be used inaccordance with this invention include for examplesym-tetrachloroethane, tetrachloroethylene, hexachloroethane,pentachloroethane, hexachloroacetone, hexachloro-l,3-butadiene,hexachloropropanone-2, hexachlorocyclopentadiene, hexachloropropylene,trichloroacryloylchloride, trichloroacetyl chloride and chloral. Of theaforementioned compounds we have found that tetrachloroethylene is aparticularly useful organic chloride activating agent for activating thealumina composite according to the process of our invention. Further,organic compounds not containing halides can be used in conjunction withsufficient chlorine or bromine, for example, ethane and ethylene.

The exact mechanism by which the alumina composite is activated is notprecisely understood especially since the process can be performed inthe absence of oxygen or an ox- 1 ygen containing. atmosphere. This isparticularly surprising since the process of a copending applicationSer. No. 495,327 filed Oct. 12, 1965 entitled Hydrocarbon ConversionCatalyst of John H. Estes and Robert M. Suggitt necessitates use of anoxygen containing atmosphere in conjunction with multicarbon organicchloride activating agents employed in that process. It is alsoconsidered particularly useful that the process of this invention makesmore economic use of the organic chloride activating agent than employedin the process of this copending application. If the chlorine or bromineorganic chloride mole ratio is greater than that specified above noappreciable increase in catalytic activity is obtained. Since excesschlorine or bromine would be entailed in providing this higher moleratio, from an economic standpoint it is generally not desirable toexceed this maximum.

With respect to temperature'we have found that a temperature of at leastabout 450 F. is desirable for preparation of a highly active hydrocarbonconversion catalyst. Temperatures less than 450 F. are generallyinsufficient to provide a highly active catalyst needed for commercialsize operations. On the other hand, temperature in excess of about 700F. tends to promote the formation of aluminum chloride and other sideproducts. Temperatures in excess of 800 F. should not be employed. Weemploy a temperature between 200 F. and 800 F most preferably 450-650 F.

The catalyst prepared by our invention can be Produced in pellet,granular, bead, or pulverulent form to facilitate its use in fixed beds,moving beds, or fluidized solid beds as is well known in the art. Thecatalyst can be prepared in situ in a hydrocarbon conversion reactor bypassing a stream of chlorine or bromine through a vessel containing theorganic compound. Preferably, however, the halide and organic compoundare added separately to the reaction zone since passing them togetherinto the reaction zone can lead to side reactions producing compounds ofsubstantially lower volatility and less reactivity in the system. Ingeneral, compounds suitable for chlorine or brominepromotion should havea reaction center,

Completely halogenated compounds are less effective than those having areaction center but may be used. The effluent istemperature between 200F. and 800 F. The effluent from the hydrocarbon conversion reactorconsists largely of hydrogen chloride and saturated chlorocarbons.Excess saturated chlorocarbons can be recycled.

For obvious economic reasons we prefer to employ chlorine together withthe multicarbon organic chloride activators. However, in certaincircumstances, one may prefer to utilize bromine as it is in liquid format room temperature.

The catalyst prepared in accordance with this invention is highly activefor alkylation at relatively low temperatures. Benzene is alkylated250-350 F and preferably within the range of 275to 315 F. Isomerizationcan be effected in either the liquid or vapor phase. Pressures fromatmospheric to the practical maximum as limited by materials ofconstruction can be used. Pressures within the range of 300 to 750p.s.i.g. have been found convenient. A liquid hourly space velocity(LHSV), that is the volume of liquid charged per hour per volume ofcatalyst, within the range of about 0.5 to 10.0 and preferably withinthe range of about 0.75 to 4.0 is suitable for this alkylation reactionusing the catalyst prepared by our invention.

In order to more full illustrate the nature of our invention and mannerof practicing the same, the following examples are presented. In theseexamples the best mode contemplated by us for carrying out our inventionis set forth.

EXAMPLE I 166 grams of l/ 16-inch alumina extrusions which had beendried at 1050 F. for 4 hours in an airstream were treated at 575 F. witha mixture of tetrachloroethylene and gaseous chlorine in a ratio of 121which mixture was introduced to the 1; alumina over a 24-hour period inan airstream passing through the alumina at a rate of 2 cubiccentimeters per hour for the tetrachloroethylene, and 6.8 cubiccentimeters per minute for the gaseous chlorine. The resultant catalystcontained 9.5 weight percent chlorine.

Alkylation of benzene with ethylene was performed by charging ethyleneand benzene into a reactor in a mole ratio of about 1:4. The reactorcontained 72 grams of the catalyst prepared by this example. Thealkylation temperature was 300 F. and the reaction mixture wasmaintained under a pressure of about 700 p.s.i.g. at a nominal chargeration of 72 grams per hour 1.0 liquid hourly space velocity). Four4-hour periods of this alkylation reaction were run. Yield data on theproduct obtained is shown below.

Ben- Ethyl- C Higher Other Period zene benzene aromatics aromaticshydrocarbons Propylene was charged to grams of the above catalystmaintained at ice temperatures at a rate of 0.04 moles per minute using500 milliliters of normal heptane as a solvent. After 3 hours, thepolymerization reaction was stopped and the solvent stripped. Theproduct was weighed. A yield of 7.6 grams of polymer having a molecularweight of 659 was real ized, the yield being about 50 percentconversion. The polymer was polypropylene.

From the foregoing it is seen that we have provided a significantlyuseful process for the preparation of a catalyst useful in alkylation ofe.g. benzene with ethylene and polymerization of lower molecular weightolefins e.g. propylene. Our alumina catalyst is also useful in theisomerization of olefin hydrocarbon. It is seen that our process can beperformed in situ i.e. within the hydrocarbon conversion reactor itselfand does not require activation of the catalyst outside the reactor withthe attendant problems of protecting from water vapor when transferringit to the hydrocarbon conversion reactor. It should be further notedthat our process can be performed to regenerate spent alumina catalystby first heating the spent catalyst to decarbonize the catalyst and thentreating in the manner of our invention. Our process can be performedwithout use of expensive chemicals, high pressures or temperatures andis thus suited for commercial operation.

The terms and expressions which have been employed herein as terms ofdescription and not of limitation, as there is no intention, in the useof such terms and expressions, of excluding any equivalents of thefeatures shown and described or portions thereof, as it is recognizedthat various modifications are possible within the scope of theinvention claimed. For instance, the process of our invention can beperformed on an alumina catalyst containing silica. in such a case, ahighly active catalyst is prepared.

What is claimed is:

l. A method for preparing a catalyst consisting essentially of aluminaand about 3.0 to about 15.0 percent by weight chlorine or bromine whichcomprises contacting alumina at temperatures between 200 and 800 F. with(1) molecular chlorine or bromine and (2) an organic compound selectedfrom the group consisting of sym-tetrachloroethane, tetrachloroethylene,hexachloroethane, pentachloroethane, hexachloroacetone, hexachloro- 1,3-butadiene, hexachloropropanone-2, hexachlorocyclopentadiene,hexachloropropylene, trichloroacryloyl chloride, trichloroacetylchloride, chloral, ethane and ethylene, wherein the mole ratio of saidmolecular chlorine or bromine to said organic compound is greater thanY/2 if X is equal to or greater than Y or greater than 0 if X is lessthan Y, where X corresponds to the number of hydrogen atoms in saidorganic compound and Y corresponds to the number of chlorine atoms insaid organic compound.

2. A process according to claim 1 wherein said composite is contacted ata temperature within the range of 450650 F.

3. A process according to claim 1 wherein said composite is contactedwith chlorine.

4. A process according to claim 1 wherein said composite is contactedwith bromine.

5. A process according to claim I wherein said organic compound ischloral.

6. A process according to claim 1 wherein said organic compound istetrachloroethylene.

7. In a process for olefin conversion selected from the group consistingof aromatic alkylation and polymerization the improvement whichcomprises contacting the reactants with a catalyst consistingessentially of alumina and about 3.0 to about 15.0 percent by weightchloride or bromine, said catalyst prepared by contacting alumina attemperatures between 200 and 800 F. with (1) molecular chlorine orbromine, and (2) an organic compound selected from the group consistingof sym-tetrachloroethane, tetrachloroethylene, pentachloroethane,hexachloroacetone, hexachloro- 1 ,3-butadiene, hexachloropropane-2,hexachlorocyclopentadiene, hexachloropropylene, trichloroacryloylchloride, chloral, ethane and ethylene; wherein the mole ratio of saidmolecular chlorine or bromine to said organic compound is greater thanX-Y/2 if X is equal to or greater than Y or greater than 0 if X is lessthan Y, where X corresponds to the number of hydrogen atoms in saidorganic compound and Y corresponds to the number of chlorine atoms insaid organic compound.

8. A process according to claim 7 wherein said olefin conversion processis aromatic alkylation and where benzene is alkylated with ethylene.

9. A process according to claim 7 wherein said olefin conversion processis polymerization and where said olefin is propylene.

10. A catalyst consisting essentially of alumina and about 3.0 to about15.0 percent by weight chlorine or bromine, said catalyst prepared bycontacting alumina at temperatures between 200 and 800 F. with (1)molecular chlorine or bromine, and (2) an organic compound selected fromthe group consisting of sym-tetrachloroethane,

5 6 tetrachloroethylene, pentachloroethane, hexachloroacetone, to orgreater than Y or greater than if X is less than Y, wherehexachloropl'opane2 Y X corresponds to the number of hydrogen atoms insaid orachlorocyclopentadlene, hexachloropropylene,

ganic compound and Y corresponds to the number of chlorinetnchloroacryloyl chloride, chloral, ethane and ethylene, I atomsin Saidorganic compoun wherein the mole ratio of said molecular chlorine orbromine 5 to said organic compound is greater than X Y/Z if X is equalm3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,607,959 Dated September 21, 1971 I JOHN H. ESTES, ROBERT M. SUGGITT,STANLEY KRAVITZ It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Column 2, line "-Y/2 should read --X-Y/2-- Column A, line 29, "-Y/2"should read --X-Y/2-- Signed and sealed this 19th day of September 1972.

(SEAL) Attest:

EDWARD M.FLETCHE R,JR. ROBERT GO'I'TSCHALK Attesting Officer-Commissioner of Patents

2. A process according to claim 1 wherein said composite is contacted ata temperature within the range of 450*-650* F.
 3. A process according toclaim 1 wherein said composite is contacted with chlorine.
 4. A processaccording to claim 1 wherein said composite is contacted with bromine.5. A process according to claim 1 wherein said organic compound ischloral.
 6. A process according to claim 1 wherein said organic compoundis tetrachloroethylene.
 7. In a process for olefin conversion selectedfrom the group consisting of aromatic alkylation and polymerization theimprovement which comprises contacting the reactants with a catalystconsisting essentially of alumina and about 3.0 to about 15.0 percent byweight chloride or bromine, said catalyst prepared by contacting aluminaat tempEratures between 200* and 800* F. with (1) molecular chlorine orbromine, and (2) an organic compound selected from the group consistingof sym-tetrachloroethane, tetrachloroethylene, pentachloroethane,hexachloroacetone, hexachloro-1,3-butadiene, hexachloropropane-2,hexachlorocyclopentadiene, hexachloropropylene, trichloroacryloylchloride, chloral, ethane and ethylene; wherein the mole ratio of saidmolecular chlorine or bromine to said organic compound is greater thanX-Y/2 if X is equal to or greater than Y or greater than 0 if X is lessthan Y, where X corresponds to the number of hydrogen atoms in saidorganic compound and Y corresponds to the number of chlorine atoms insaid organic compound.
 8. A process according to claim 7 wherein saidolefin conversion process is aromatic alkylation and where benzene isalkylated with ethylene.
 9. A process according to claim 7 wherein saidolefin conversion process is polymerization and where said olefin ispropylene.
 10. A catalyst consisting essentially of alumina and about3.0 to about 15.0 percent by weight chlorine or bromine, said catalystprepared by contacting alumina at temperatures between 200* and 800* F.with (1) molecular chlorine or bromine, and (2) an organic compoundselected from the group consisting of sym-tetrachloroethane,tetrachloroethylene, pentachloroethane, hexachloroacetone,hexachloro-1,3-butadiene, hexachloropropane-2 ,hexachlorocyclopentadiene, hexachloropropylene, trichloroacryloylchloride, chloral, ethane and ethylene, wherein the mole ratio of saidmolecular chlorine or bromine to said organic compound is greater thanX-Y/2 if X is equal to or greater than Y or greater than 0 if X is lessthan Y, where X corresponds to the number of hydrogen atoms in saidorganic compound and Y corresponds to the number of chlorine atoms insaid organic compound.